Fate of Homologous Adult Spleen Cells injected into New-born Mice

Abstract

DURING a series of experiments involving radiation chimæras, it became increasingly evident that it would be necessary to consider the results in terms of immunological tolerance of the actively acquired type. At the time a cytological marker was being used for tracing donor cells in the radiation chimæras, following the technique of Ford, Hamerton, Barnes and Loutit¹. It was decided to use the same marker in tracing cells injected into new-born animals in order to determine, by a direct method, to what extent chimærism is a necessary adjunct to tolerance. There is considerable circumstantial evidence that this is indeed the case^2,3.